stedman



No. 626,3. Patented-June 6, I899.

W. H. STEDMAN. SEWING MACHINE.

iApplication filed May 20, 1897.)

No Model.) 2 Sheets-S'heet I.

'Patented June 6, I899.

W. H. STEDMAN.

SEWING MACHINE.

(Application filed may 20, 1897.)

2 Sheeis$heet 2.

- 1N0 ModeL) m2 NORRIS warns 0o, moTo-LwHa. msnmarou, n. c.

UNITED STATES PATENT OEEIcE.

WILLIAM H. STEDMAN, OF HARTFORD, CONNECTICUT, ASSIGNOR TO THE MERROIVMACHINE COMPANY, OF SAME PLACE.

SEWING-MACHINE.

SPECIFICATION forming part of Letters Patent No. 626,311, dated June 6,1899.

Application filed May 20, 1897. Serial No. 637,439. (No model.)

To (LZZ whom it may concern:

Be it known that I, WILLIAM H. STEDMAN, of Hartford, in the county ofHartford and State of Connecticut, have invented certain new and usefulImprovements in Sewing-Machines; and I do hereby declare the followingto be a full, clear, and exact description of the same, reference beinghad to the accompanyin g drawings, forming a part of this specification,and to the figures and letters of reference marked thereon.

This invention relates to improvements in the looping or stitch-formingmechanism of double-thread chain-stitch sewing-machines, and has for itsprincipal objects the production of a looping mechanism combining theelements of rapidity, durability, certainty of action, and simplicitytogether with a wide range of adjustability.

Sewingmachines of the class referred to are usually furnished with afabric-penetrating needle and a looper carrying the second or otherthread, said looper being reciprocated in two directions on intersectinglines passing on one side of the needle to enter the loop of threadcarried thereby and shifting to the opposite side of the needle,presenting a loop of the second thread in position to be penetrated bythe needle. These more or less complex motions in different planes or.in lines which are not planes involve mechanical difficulties and aredetrimental to speed and durability.

According to my present invention I make use of two instruments inaddition to the needle, each of said instruments being arranged toreciprocate in but a single plane, the one performing its excursions ina plane 011 one side the needle to enter the loop of needlethread andlocate its position, while the other, carrying the under thread,performs its excursions in a plane intersecting the loop onthe'first-named instrument and extending on the opposite side of theneedle to carry a loop of under thread through the loop of needlethreadand present it in position to be entered by the needle as the latterpasses through the fabric.

In illustrating the preferred embodiment of my invent-ion I have shownit in its sim plest adaptation'-that is, in connection with avertically-reci proeatin g eye-pointed needle; but inasmuch as theimprovements have relation solely to the looping mechanism it is obviousthat the latter can be substituted for corresponding parts of theunderlooping mechanism found in various styles and kinds ofsewing-machines In the accompanying drawings, Figure 11s a frontelevation of the machine. Fig. 2 is a sectional view on the line 0000,Fig. 1, showing the looper mechanism. Fig. 3 is a plan view of thelooper mechanism. Figs. 4, 5, 6,

' 7, and 8 are diagrammatic views illustrating different stages of thestitch-forming operation. Fig. 9 is a sectional View, on an enlargedscale, of the loop -taker and secondthread carrier, showing a loop ofneedlethread on the loop-taker. Fig. 10 is a top View of a modified formof the loop-taker. Fig. 11 is a sectional view, on an enlarged scale,through the modified loop-taker and second-thread carrier, a loop ofneedle-thread being shown on the loop-taker.

Similar letters and numerals indicate like parts in the several figures.

For the purpose of furnishing a comprehensive illustration of one formin which my present invention has been practically embodied I have shownit as applied to a sewing-machine of ordinary construction, but havingthe new looping mechanism substituted for the old. In said machine A isthe bed; B, the gooseneck; C, the main shift; D, the driving-pulley; E,the eccentric for driving the needle-bar; F, the eccentric connection;G, the needle-lever; H, the needle-bar; I, the work-plate; J, thepresser-foot; h, the fabricpenetrating needle; ab, tensions; b g h,takeup eyes for needlethread; a, take-up spring for under thread. Allthe foregoing-enumerated parts being in general form and action similarto corresponding parts in common use insewing-machines,furtherexplanation is unnecessary. I

The improved looper mechanism includes as its principal elements aloop-taker 12 and an under-thread carrier 1, both located beneath theWork-plate and each reciprocating in a single plane, the path of theloop-taker ICQ 2 l I l 1 626,311

12 lying to one side-of the needleand that of the und er threadcarrier 1lying on the opposite side of the needle and intersecting the path'ofthe loop-taker, the arrangement beings uch that the loop-taker duringits forward motion toward the needlewillpass in close proximity to theascending needle, between the latter and its thread, en t'ering'andspreading the loop of needle-thread across the path of theunder'-thread.'carrier, which latter is advanced through theneedle-thread loop held by the loop-taker and, passing on the oppositeside of the path of-the needle, carriesits f under thread into positiontobe engaged by the needle during its next descent through the fabric.

I The transferof the needle-thread loop from the side of the needle onwhich it is t-ak'en by the {loop-taker into the'path-o'f the under"-t'h'readcarri'e'r, the latter moving in a plane 1 on the sid'e ofthe-need 1e opposite to the loop taker, is effected by theloop-takeralone, the

latter being-so sh ap'ed that it Will operate upon the loop ofneedle-thread {to spread or d ijve'rt' it lat-erall y.

So-far-asthe e'n'tering'or pointed end'of the l-oop-taker' is concerneditis only necessary that it s'hall be of suilable'form to enter the loopat the side of :theneedle as 'the latter aseends ina in'ann er co'mm'o'nin loopers in general extension of the looper on'the sideneares't"theneedlesufficient in amount to efiect a's preadingo'rdiversion of the loopof needlethread in a'dvance of the under thre'adcarrier,

so that the latterwhile moving in a single plane'ontheside of the needleopposite to'the loop-taker and in such proximity to the need'le-astopresen't'the under thread thereto will surely 'enter and pass into theloop of needleth'read. "Inits preferred form for this purpose fthelooptaker is provided with a flat narrow blade 20, lying substan'tiallyparallel vvith the needle, and a lateral extension or web 2l,beginningjust in 'rear of the point and increasing on a gradual inclin'ein curvefrom-the planesurfa'ce 20(see Fig. 3) until' attainingd-tsxfulldimensions, as at 22, at or neariwhich poi'ntthe cross-sectionwill beapproxim'ately as illustrated in Fig. 9.

The. under face or edge of the loop-taker is .provided Withaslightshoulder 23,Which acts as a drag on thethread during a part of thebackwardmotion of the loop-taker; but said shoulder is not so pronouncednorsufticien'tl y abrupt-'to act as-a hook in retaining the loop. On thecontrary, while delaying-slightly, it freel'y perimits the-final-escapeof the loop when theloop-taker 'is sufficiently retracted. Theloop-taker is also preferably furnished witha=slightswell orenlargement24 on the side away from the needle,betweenthe point and the apex of theincline 21, the purpose of -which is to obtain an. increased supply ofneedle-thread while the latter is loose in the form of a loop at theside of the needle beneath the Work-plate and fabric, thus securing afullness of loop nearly or quite sufficient to permit the easy passageof the incline 21 through said loop. This enlargement 24 also actstofill the needle-thread loop, and thus controls its position While thelooptaker is being Withdrawn from the loop.

It is not essential, although desirable, that the loop-taker should beprovided with a laterally-projecting Web 21 to eltect the diversion ofthe needle-thread loop, for a similar result can be obtained by bendingor curving the loop-taker bodily, so that the portion in rear of thepoint wi-llsoccupy a position toone side-of the needle and in linewith'the underth-read carrier, as indicated in Fig. 10.

The operalingend or horizontal portion'of the under threadcarrier 1 isformed with an eye'25 near its point, a groove 26 alongits front-siderunning 'rearwardly to anothereye 27 for the passage of the underthread.

Thelooptalrer 12, Whether reciprocating-in a'cur-ved or right line, hasits motions in a single plane on one side of the needles line i or pathof reciprocation below the fabric,with the loop-diverting portion21-m0vin g in a path -intersecting or crossing that of the needle, whilethe under-thread carriers plane of recipro'cation is 'onthe oppositeside of the needle and co'incides'wi'th or intersects the plane ofmovement of the loop-diverting portion 21 of the loop-taker 12, wherebysaid lowerthread carrier is causedto penetrate the'loop of needle-thread borne by the loop-taker. It is obvious that it is immaterial to theoperation of these looping devices Whether the loop-taker andlower-thread carrier move in straight or curved paths, or from'the-sameor opposite sides of the needle, so long as their motions areperformed'in planesand do away with sidewise or' shogging motions inaddition to their longitudinal reciprocating movements; but I prefer tooperate both instrumentsfronithesame side and to mount them upon rockingsupports, so that they will move in curved paths, as by this arrangementa simple and effective driving mechanismcan readily'besupplied and'ampleprovision made for adjustment.

The preferred form and arrangement of dri-vi-ng mechanism areillustrated in the drawings, wherein a is a stationary rod disposedtransversely of and below the plane of its main-shaft O,- said rod beingsuitably held at i-ts'e'nds insupports 5 6. ,Ati1bularrock-shaft orsleeve 3, inountednpon rod 4, is-furnished at one end' with an arm 2,provided with a socket and set-screw or equivalent holder for the'shankoflower-thread carrier 1. To the opposite end of sleeve 3 isadjust-abl y attached an arm 7, bearing a ball 8, which latteris'received in'a socket 9 at the lower end of eccentric connection10,theup'per'end of 'saidconnection engaging a spherical eccentric 11 ona second tubular rock-shaft or sleeve 14, the

latter taking its bearing upon the periphery of sleeve 3 and beingfurnished with an adjustable lever or arm 15, hearing ball 16, en-

gaging socket 17 in the lower end of eccentric connection 18, the upperend whereof encircles the spherical eccentric 19 on main shaft 0.

.lVhile it is obvious that separate supports might be provided for thesleeves 3 and 14, there are some advantages secured by mounting onesleeve on the other and supporting them upon a single red, the number ofparts being reduced, the arrangement more compact, and the lubricationsimpler and more effective, all of which are desirable features in ahigh-speed machine of this kind. Ample provision is thus made foradjusting the looptaker and lower-thread carrier with respect to eachother and the needle. Thus both radial and lateral adjustments may bemade at the point of attachment to the sleeves, while the position ofeach instrument with reference to its driving-eccentric can be varied byturning the arms 7 or 15 on the sleeves.

It will of course be understood that the usual or any approved tensionsand take-ups are or may be employed, likewise a fabricfeeding mechanism,and that instead of a straight reciprocating needle other forms ofneedle and needle-driving mechanism adapted for the purpose may beutilized. Ilence as to these matters the forms shown in the drawings aremerely illustrative and not of the essence of the present invention,which has to do mainly with the looping devices and mechanism. 1

The operation of the looping devices in their preferred form will bereadily understood by reference to Figs. 4 to 11, inclusive. Let it beassumed that the needle and under-thread carrier have been properlythreaded and that the seaming operation has been arrested with theneedle at or near its lowest position. The parts will then occupyrelative positions approximately as shown in Fig. at. The machine beingstarted up, the needle ascends, the looptaker advances and is followedby the underthread carrier until the parts reach positions approximatelyas shown in Fig. 5, the loop of needle-thread having been entered by andretained upon the point of the loop-taker. As the needle is withdrawnfrom the fabric the loop-taker advances through the loop ofneedle-thread, expanding the latter and diverting it laterally in frontof the under-thread carrier, which latter advancing at the same timeprotrudes its point through the loop of needlethread, as indicated inFig. 6. At this stage the loop-taker has passed its shoulder 23 beyondthe thread, and the loop surrounds both the loop-taker and theunder-thread carrier, Figs. 9 and 11. The loop-taker occupies a positionslightly in advance of the under-thread carrier, so that when the needlearrives at or near the extreme of its upward motion and the loop-takeris at or near its most advanced position the parts will assumeapproximately the positions represented in Fig. 7. The needle now beginsto descend and the loop'taker to withdraw, followed shortly by theunderthread carrier; but during this backward mo tion of the loop-takerthe needle-thread loop encounters shoulder 23, which drags suitieientlyto divert the loop from the path of the descending needle, the latterpassing down between the loop-taker near its point and the inner side ofthe under-thread carrier in rear of its eye 25, thereby being caused toenter between the loop of needle-thread and that portion of the underthread extending from the fabric or the previous stitch to the eye ofthe under-thread carrier, Fig. 8, so that as the loop-taker andunder-thread carrier by their continued rearward motion are withdrawnentirely from the needle-thread loop a loop of under thread will be castupon the needle, Fig. 4, preliminary to the next advance of theloop-taker. (See Fig. 5.)

It will be observed that there is an interval between the point or blade20 of the loop taker and the inner side of the under-thread carrier forthe passage of the needle, and that this interval can be increased ordiminished by adjustment to suit needles of various sizes, and, further,that this interval is bridged in rear of the point of entrance of theneedle between the loop-taker and the u nderthread carrier by thelateral extension or web 21 of the loop-taker, thus insuring theentrance of the under-thread carrier into the loop of needle-thread andof the needle into the loop of under thread.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-- 1. In a double-thread chain-stitchsewingmachine, the combination with the needle of a looping mechanismcom prising a loop-taker and an under-thread carrier, each reciprocatingin a single plane, and on relatively opposite sides of the path of theneedle, said looptaker being provided with a loop-diverting surfaceextending into the plane of motionof the under-thread carrier fordiverting the loop of needle-thread into the path of the under-threadcarrier; substantially as described.

2. In a sewing-machine such as described, the combination With areciprocating eyepointed fabric-penetrating needle, a reciprocatingloop-taker movable in a plane on one side the needle and provided with alateral extension or loop-diverter intersecting the path of the needle,and an under-thread carrier reciprocating in a plane 011 the oppositeside of the needle and intersecting the plane of movement of thelooptaker, whereby the loop-taker is caused to enter the loop ofneedle-thread and divert it into the path of the under-thread carrierand the latter entering the loop of needle-thread delivers a loop of itsthread to the needle; substantially as described.

3. Ina sewing-machine such as described, the/combination with areciprocating threadv carrying needle, of aloop-takerreciprocating in a-single plane, substantially parallel with and to one side of the needlewhen beneath the fabric, said loop-taker beingfurnished witha-loop-diverting surface extending laterally across the path of theneedle, and an under-thread carrier reciprocating in a single plane onthe side of the needle opposite the loop-taker, the path of the said thread-carrier intersecting the plane of movement of the loop-divertingsurface'of the loop-taker; substantially as described. I 4. In asewing-machine such as described, the combination with a'reci'procatingthreadcarrying needle, of a'lo'op-t-ak er and an underth read carrierreciprocating in parallel plan es transversely oft-he axis ofthe'ne'edle and on opposite sides thereof, said loop-taker beingprovided with a loop-detaining shoulder and a loop-di'verter or lateralextension operating to divert the needle-thread loop from the sidenearest the loop-taker into thepath of the under thread carrier;substantially as described.

' -5. In aseWing-machine such as described, thecombination with thereciprocating need le of the loop-taker reciprocating on 'one sideofth'e needle and provided with the blade, a lateral extension orloop-diverting surface and aloop-detaining shoulder and the undert'hreadcarrier reciprocating on the opposite side of the needle, saidunder-thread carrier moving in a path above the loop-diverting surfaceof the loop-taker, to enter the loop of its thread to the 6.. In asewing-machine such as-described the combination with a reciprocatingthreadcarrying needle, of the loop-taker and underthread carrier,mountedto reciprocate in parallel planes upon a common axis, the looptakermovingon "one side of the needleand the under-'threadcarrier on theopposite side thereof; substantially as described.

dle and provided with a loop-deflecting sur- L face in rear :of itsentering end, and the laterally and radially adjustable under-threadcarrier likewise supported to reciprocate in a single plane on the sideof the needleopposite to the loop-taker; substantially as described.

8. In a'sewing-machine such as described the combination with the needleand main shaft,of the loop-taker and eye-pointed underthread carrier,each pivotally supported to reciprocate in a single plane about an axislying transversely to the'main shaft, with connecting mechanism fortransmitting motion from the main shaft to the said loop-taker andthread-carrier; substantially as described.

9. In a sewing-machine such as described, the combination with theneedle and main shaft, of the loop-taker 1'2 and under-thread carrier 1-each secured to a separate rockshaft supported and operating beneaththework-plate, two eccentrics on the main shaft and adjustable drivingconnections intermediate each rock-shaft and its eccentric; sub

stantially as described.

10. In a sewing-m achine such as described the combination wi th theneedle, of "the looper mechanism, the. same comprisinguthe two sleevesor hollow rock-shafts arrangedone Within the other andsupportedupona-central rod or axis, a driving-eccentricconnected to each sleeve forrocking the latter,-the looptaker supported radially on onesleeve andthe under-thread carrier similarly supported on the other sleeve;substantially as described.

WILLIAM H. STEDMAN.

Witnesses: WINFIELD O. GRAHAM, ROBERT P. SMITH.

